The present invention relates to a method for detection and differential diagnostic determination of leukemic cells by selective staining of leukemic blood cells.
The known staining methods for leucocytes are unspecific because they stain both normal and leukemic cells. For diagnosis of leukemia it has hitherto been necessary to demonstrate a pathogenic increase in the number of leucocytes by determining the number of leucocytes in the blood circulating in the vessels. Diagnosis of leukemia via the determination of changed enzymatic activities of leukemia cells is time-consuming and expensive in terms of apparatus. A staining method for leukemic cells using merocyanine dyes has been disclosed in Cell 13, 487 (1978). Evaluation is by fluorescence microscopy. This method is disadvantageous since it requires a fluorescence microscope which is considerably more expensive than a normal microscope. Thus, such instruments are not available in all locations where it could be of interest to carry out a leukemia test. A further disadvantage is that stained and unstained cells cannot be evaluated at the same microscope setting; this makes the evaluation involved.